Garmin 250 B&w

[silverdoctor]

4 years ago I got the bright idea to "upgrade" my front fish finder. I purchased the Garmin 250 to replace a Lowrance X51 (same model is in the dash). the depth reading has started flashing in and out (Mostly out-no reading). The temperature guage is reading about 4 F low. Misplaced the manual (expect to find tomorrow). I wished I still had the X51; this Garmin was a poor choice.

Should mention the transducer is mounted on the trolling motor.

Does anyone have experience with this unit or brand? ideas on sources of problem?

Thanks for any input.

[Braided Line]

I`ve had 3 or 4 different brands over the years and one by one they all died. Usually one function goes, then it`s all down hill from there.

Bought a Garmin 140 a couple years ago and so far......so good. This past week my olderst F/F died. So, today I ordered a new Garmin 140 from Amazon. Rest assured if the "140 " didn`t work ok, I`d be a little leary of buying another.

The only problem is if you mount the transducer on your Trollimg motor and get into shallow water it`s the first thing to hit bottom. Sets off the motor some due to the mount design. On the plus side, you can mount the transducer on the hull or T/M.

[silverdoctor]

BraidedLine: Thanks for taking the time to respond. I've returned all settings to factory (dry); can't wait to see whats going on.

My dash unit and the Garmin talk to each other (intererence). This is at least part of the problem. I checked the cable for nicks, etc. seems ok.

At one point the other day, I had depth readings of 4000 feet (yikes).

Operator error may be a problem here as well.

Hope I don't have to buy another unit.

ken

[BobP]

Ken - Sent a separate PM to you. I've used a Garmin 240 for the last 8 yrs and it has been faultless. Had it on the helm, moved it to the TM when I got a big Humminbird SI sonar and it has continued ticking away perfectly. I removed a Lowrance 51 from my TM when I got the boat - and threw it in the trash! No comparison to the screen detail and performance of a Garmin! I'd be using all-Garmin all the time except for the fact that when I moved up to a GPS/mapping unit, I wanted one from a company that used Navionics map cards versus proprietary map cards like Garmin does. 2 problems I've had with the sonar in 8 years, neither of which were Garmin's fault. One, the cable on the transducer eventually broke from being torqued back and forth on the TM shaft. Second, the connectors on the power wires to the sonar head became corroded and were not passing enough amperage. That was hard to find since 12V was still being indicated on a voltmeter! But easy to fix.

If you can find a Garmin sonar head to borrow, you can easily diagnose your problem. Plug your existing cable into the loaner. If it works, your sonar head is broken. If it shows the same problems as you are having on your sonar, your transducer is going bad or you have an electrical problem. In my experience, most sonar failures are due to the transducer. Some are caused by guys leaving their sonar heads on the boat, stored outside under a boat cover. The extreme changes in temp eventually defeat the seals in the unit. Symptom = fogged screen, followed by head failure. If your electrical connection to the sonar has been in place for awhile and was not done with marine grade connectors (melted plastic interior/heat shrink exterior), it's worth re-doing them to get guaranteed good power to the unit. Lastly, check the connection to the battery or the fuse panel where the power originates. I've also heard of intermittent problems caused by a loose or defective fuse inside an in-line fuse holder, if that's what your unit employs.

Edited April 15, 2010 by BobP

[silverdoctor]

Thank you for the great writeup. I think the unit is ok now that operator error has been eliminated.

I will keep your post for future diagnostic endeavors.

Have a great Spring fishing.

ken